Distant volume control



June 1, 1937. L. D. STRONG 2,082,745

DISTANT VOLUME CONTROL Filed Sept. 22, 1930 Patented June 1, 1937 DISTANT VOLUME CONTROL Lawrence D. Strong, Maywood, Ill., assignor of one-half to Glenn S. Noble, Chicago, Ill.

Application September 22, 1930, Serial No. 483,708

10 Claims. (or. 179-1001) -UNlTED STATES PATENT OFFICE This invention relates to means for controlling the volume or output for sound reproducing apparatus to the loud speakers and is particularly applicable for use in theaters producing so-called talking moving pictures. In accordance with a common practice the sound reproducing apparatus in such theaters is arranged in the operators booth with wires leading to the loud speakers arranged adjacent to the screen, or at such points as appear desirable. The moving picture operator controls the sound reproducing apparatus but has no direct means of knowing how the sound or tones are delivered to the people in the audience. In order to provide some sort of control, a person who may be considered as a'director, is seated in the theater and if the volume is too great or too small will signal to the operator to decrease or increase the same. However, this is not satisfactory as, by the time the operator makes the change in control, the necessity therefor may have passed and the general effect may not be pleasing. Constant changes in the volume are usually necessary due to variations in the recording of the sound and also due to changed conditions in the theater as by the increase in the number of people in the audience.

In accordance with the present invention, I provide means whereby the volume from the sound reproducing apparatus may. be controlled directly by the operator and may also be controlled directly by a person at a distance from the apparatus as for instance, a person seated in the theater or a moving picture house.

The objects of this invention are to provide an improved distant .volume control for sound reproducing apparatus; to provide means whereby a person seated in the auditorium of a theater may directly control the output to the loud speakers or sound reproducing apparatus; to provide a dual control for sound reproducing devices; to provide an auxiliary distant control for a sound reproducing apparatus which may be operated independently of the usual knob or control means; and toprovide such other advantages in operation and improvements in construction as will be described more fully hereinafter.

In the accompanying drawing illustrating this invention;

Fig. 1 is a front view with parts broken away to show the interior construction;

Fig. 2 is avertical sectional view also with parts broken away;

,'Fig. 3 is an enlarged detail of one of the ratchet pawls Fig. 4 is a detail of the auxiliary or stub shaft and parts connected therewith; and

Fig. 5 is a diagram of the circuits for the controlling devices.

As shown in the drawing, 6 indicates a cabinet 5 of any suitable sound reproducing apparatus, such as ordinarily employed in talking moving picture theaters and which is provided with a shaft 1 for actuating the volume control device or devices such as a rheostat or the like. This shaft is usually provided with a knob 8 for turn-'- ing .the same manually, such knob having a pointer 9 which coacts with a suitable scale or dial for indicating the position of the controlling devices.

A plate III is secured to the cabinet 6 and carries the auxiliary controlling devices. A stubv shaft H projects through a hole l2 in this .plate and has a bearing therein. The inner end of the shaft is provided with a slot I3 to receivethe 2 tongue or projection M on the shaft 1 in order to make a coupling. The outer end of the shaft is carried in a bearing IS on a bracket l6 secured to the plate II]. A cover I 1 encloses the operating devices and the outer end of the shaft ll projects through this cover and is provided with pins I 8 for engagement with holes in the knob 8 so that this knob may be applied to the stub shaft in the same way as originally applied to the shaft 1. The cover 11 is provided with a scale or dial l 9 which cooperates with the pointer 9 in the usual manner.

A ratchet wheel or toothed wheel 20 is secured to the shaft ll sothat the shaft may be turned thereby as well as by the knob 8. This wheel is adapted to be turned in either direction by suitable pawls operated by electro-responsive deyices. In the present instance, I arrange solenoids 2i and 22 on either side of the wheel. These solenoids are provided respectively with cores or rods 23 and 24 which extend upwardly through bearings 25 and 26 on the plate Ill. These cores are normally held in raised position by means of springs 21 and 28 which engage with the bearings and with washers 29 and 30 at the upper ends of the respective cores. These cores are preferably flattened where they pass through the bearings in order to prevent rotation. Pawls-3l and 32 are pivoted to the respective cores 23 and 24 and are adapted to 5 engage at 4 times with the ratchet wheel 20'. These pawls are mounted in slots or recesses in the shafts thereby providing shoulders 33 and 34 which prevent the pawls from swinging upwardly, with respect to the cores. beyond a predetermined distance, or at approximately right angles to the cores. These pawls are provided with springs and 36 which tend to hold them normally in raised position as shown particularly in Fig. 3. Stops'or abutments 31 and 38, comprising angle plates secured to the back or plate to, are arranged adjacent to the ratchet wheel and serve to throw the pawls out of engagement therewith when the cores are raised to their upper or normal position by the springs, as shown in Fig. 1. The travel of the cores or rods 23 and 24 when actuated by the solenoids, may be adjusted by means of set screws 39 and 40 arranged within the path of the lower ends of the rods.

It will be seen that this arrangement is such that the operator may control the volume by means of the knob 8 which turns the rheostat or the like in the usual manner. However, if the solenoid 2| for instance, is supplied with current, its core or armature will be attracted and will be drawn down against the tension of the spring 21. As the pawl 3| passes away from the stop 31 it moves into engagement with one of the teeth of the ratchet wheel 20 and a con-- tinued movement of the core causes the pawl to rotate the ratchet wheel a predetermined amount, which rotation may be controlled by the adjusting screw 39. When the current is'cut off, the core again moves upwardly to normal position and the pawl is in condition for again actuating the ratchet wheel. Thus by repeated impulses to the solenoid,'the ratchet wheel, and

consequently the volume control device actuated thereby may be turned anticlockwise. In a similar manner, by actuating the solenoid 22 the parts coacting therewith will cause the ratchet Wheel to be turned in a clockwise manner so that by actuating the respective solenoids, the control may be manipulated the same as by turning the knob.

The circuit arrangement for the person actuating this control as for instance, a person seated in the theater, is shown in Fig. 5. Such person or director is provided with two push buttons or switches ll and 32 which are arranged in any convenient manner, as for instance, so that he may hold them in his hand and circuit wires connect these switches with a source of electric supply and with the solenoids 2i and 22. One Wire E3 leads from the source of supply and is connected directly with the two solenoids. The other wire 6% from the source of supply has one branch leading to one terminal of the switch 6!. The other terminal of this switch is connected by wire 36 with the solenoid M. A second branch ll leads from the wire 46 to one terminal of the switch :32 and the other terminal of this switch is connected by wire 68 with the solenoid 22. When the directoractuates the switch ll the current will be supplied as above suggested to the solenoid Zl; the circuit being through wire 43, solenoid 2!, wire 56, switch M, wire it and wire 34. When the director actuates the push button or switch 52 the current is supplied to solenoid 22, the circultbeing through wire solenoid 22, wire 68, switch 12, wire 31 and wire M.

It will be understood that push buttons or switches t! and 62 may be arranged at any suitable point or points so that the person listening to the sound reproduction may have constant and accurate control of the volume thereof and may modulate the same as it appears desirable to secure the best acoustical effect.

While I have shown and described a practical embodiment of my invention it will be apparent to those familiar with this art that the particular operating instrumentality may be modified or different types used without departing from the scope of the invention and changes may also be desirable to apply the control to difierent types of sound reproducing apparatus. Therefore I do not wish to be limited to the particular arrangement herein shown and described except as specified in the following claims in which I claim.

1. The combination with a rotatable shaft for actuating a volume control of the character set forth, of a ratchet wheel, solenoids arranged adjacent to either side of the wheel, upwardly extending cores for said solenoids, resilient means tending to hold said cores in raised position, pawls carried by the cores and adapted to coact with the wheel, means for causing the pawls to disengage the wheel when in normal position, adjustable stops for the cores, a switch for each solenoid adapted to be positioned at a distance therefrom,andcircuits from a source of electricity to the respective solenoids, each circuit including one of said switches, the arrangement being such that the opening and closing of the switches will cause the respective solenoids to actuate their cores and thereby cause the pawls to rotate the wheel in opposite directions.

2. The combination with the cabinet of a sound reproducing apparatus, including a volume control, of a plate adapted to be secured to the cabinet, a stub shaft mounted on said plate and coacting with the volume control, a knob for turning said shaft, a ratchet wheel secured to said stub shaft, two solenoids arranged adjacent to the wheel and having upwardly extending cores, springs tending to hold said cores in normally raised position, pawls adapted to be actuated by the cores and coacting with the ratchet wheel, one being adapted to move the wheel in one direction and the other in the opposite direction, a cover for said solenoids and coacting mechanism, a dial on said cover, a pointer on the knob coact ing with the dial, circuits from a source of electricity to the respective solenoids and switches arranged in said circuits, and adapted to be manually operated whereby the operator may cause either of said solenoids to be actuated to turn the shaft to regulate the volume of the output of the reproducing apparatus, substantially as described.

3. The combination with the volume control device, of a sound reproducing apparatus comprising a rheostat or the like, having the usual manually operated means for adjusting the same, including a shaft, of a manually controlled electrically operated adjusting means operating independently of said manual adjusting means, comprising a ratchet Wheel secured to said shaft, solenoids arranged adjacent to the wheel, pawls actuated by said solenoids, one being adapted to turn the wheel in one direction and the other in the opposite direction, a source of electricity, circuits from said source of electricity to the respective solenoids, and manually operable switches in said circuits.

4. The combination with the volume control device of a sound reproducing apparatus having the usual manually operated means for adjusting the same which includes a rotatable member, of a ratchet mechanism associated with said rotatable member for rotating the same in opposite directions, electro-responsive means for actuating said aoaa'ma operated independently of said manual adjust ing means.

5. The combination with the volume control device of a sound reproducing apparatus having the usual manually operated means for adjusting the same, of an independently operable adjusting means comprising electro-responsive mechanism for adjusting said volume control, a switch adapted to be positioned at a distance from the volume control, a source of electricity and a circuit from saidsource of electricity including the switch and the electro-responsive de vice,the arrangement being such that the actuation of the switch will cause the operation of the electro-responsive device which is adapted to act independently of the manual adjusting means.

6. Control means for adjusting the tuning mechanism of sound reproduction apparatus comprising a rotatable disc; interconnecting means between said disc and said tuning mechanism for operating said tuning mechanism; a,;pair of solenoids with means enageable with said disc for rotating said disc in opposite directions upon alternate momentary energization of said solenoids;

means for selectively energizing said solenoids and means for manually operating said disc in opposite directions.

'7. Control means for adjusting the volume control mechanism of sound reproduction apparatus comprising a rotatable device, interconnecting means between said device and said control mechanism for operating the latter, a pair of solenoids with means engageable with said device for rotating said device in opposite directions upon alternate momentary energization of said solenoids, means for selectively energizing such solenoids, and means for manually operating said device in opposite directions.

8. In combination with the volume control element of a sound reproducing apparatus usable in connection with motion pictures, of 'inanual operating means for adjusting the volume control element, and electrical operating means for adjusting said volume control element independently of the manual operating means at a distance from the sound reproducing apparatus, said electrical operating means comprising an electric circuit, solenoid means responsive to impulses of the electric current in the circuit for adjusting the volume control element, and a circuit make and break device for controlling the electric. circuit.

9. In combination with the volume control element of. a sound reproducing apparatus usable in connection with motion pictures, of manual operating means for adjusting the volume control element, and electrical operating means associated with the manual operating means for adjusting the volume control element independently of said manual operating means at a distance from the sound reproducing apparatus, said electrical operating means comprising an electric cirfrom the sound reproducing apparatus comprising an electric circuit, means including a solenoid responsive to impulses of theelectric current in the circuitfor adjusting the volume control element in association with but independently of the manual operating means, whereby either is operable independently of the other, and a circuit make and break device for controlling the electric circuit to the solenoid.

LAWRENCE D. STRONG. 

